Don't let your dog fear the great outdoors. K9 Advantix II kills and repels fleas, ticks and mosquitoes too. It works through contact, so they don't have to bite your dog to die. Benefits: Kills and repels Starts to kill through contact within 12 hours ? so pests don?t have to bite your dog for it to work. Vet-recommended No prescription needed. Effective on dogs and puppies 7 weeks of age and older that weigh 4 lbs. or greater. Easy-to-apply Goes on in seconds. Apply drops directly on your dog's skin ? no hard-to-swallow pills. 30 days of waterproof protection Apply K9 Advantix? II monthly. It becomes waterproof after 24 hours. Unlike most competitors, K9 Advantix II not only helps repel fleas and ticks for four weeks; it also kills and repels mosquitoes that may transmit heartworm disease and West Nile virus.